From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 51A13C636D4 for ; Mon, 13 Feb 2023 23:55:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229647AbjBMXzM (ORCPT ); Mon, 13 Feb 2023 18:55:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60480 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229489AbjBMXzL (ORCPT ); Mon, 13 Feb 2023 18:55:11 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 067161B7 for ; Mon, 13 Feb 2023 15:55:10 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id A8BE8B818FF for ; Mon, 13 Feb 2023 23:55:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 67D5BC433D2; Mon, 13 Feb 2023 23:55:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1676332508; bh=59pNvKH6ir1+NOcEbBEbqZpHb/ooChO0rsTtRCwaUYg=; h=Date:To:From:Subject:From; b=Igtf5b2DkvvOuLleLs24LnGOCrIZGq35+R4+OtZTCJegaUVVsMu87/dQR5JnU5PE5 2iH+P1QgG7tzyVWquwyr9s/Ymch2XYx9kqpVW5m87z/V4quzTsyoUPDYIhvPFxWXMD bp3g/ysyCpoKukb8MHBTuNGrc5RGJDxTdEdJEKz4= Date: Mon, 13 Feb 2023 15:55:07 -0800 To: mm-commits@vger.kernel.org, willy@infradead.org, m.szyprowski@samsung.com, alex@ghiti.fr, vishal.moola@gmail.com, akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] mm-khugepaged-fix-invalid-page-access-in-release_pte_pages.patch removed from -mm tree Message-Id: <20230213235508.67D5BC433D2@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The quilt patch titled Subject: mm/khugepaged: fix invalid page access in release_pte_pages() has been removed from the -mm tree. Its filename was mm-khugepaged-fix-invalid-page-access-in-release_pte_pages.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: "Vishal Moola (Oracle)" Subject: mm/khugepaged: fix invalid page access in release_pte_pages() Date: Mon, 13 Feb 2023 13:43:24 -0800 release_pte_pages() converts from a pfn to a folio by using pfn_folio(). If the pte is not mapped, pfn_folio() will result in undefined behavior which ends up causing a kernel panic[1]. Only call pfn_folio() once we have validated that the pte is both valid and mapped to fix the issue. [1] https://lore.kernel.org/linux-mm/ff300770-afe9-908d-23ed-d23e0796e899@samsung.com/ Link: https://lkml.kernel.org/r/20230213214324.34215-1-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) Fixes: 9bdfeea46f49 ("mm/khugepaged: convert release_pte_pages() to use folios") Reported-by: Marek Szyprowski Tested-by: Marek Szyprowski Debugged-by: Alexandre Ghiti Cc: Matthew Wilcox Signed-off-by: Andrew Morton --- --- a/mm/khugepaged.c~mm-khugepaged-fix-invalid-page-access-in-release_pte_pages +++ a/mm/khugepaged.c @@ -511,11 +511,17 @@ static void release_pte_pages(pte_t *pte while (--_pte >= pte) { pte_t pteval = *_pte; + unsigned long pfn; - folio = pfn_folio(pte_pfn(pteval)); - if (!pte_none(pteval) && !is_zero_pfn(pte_pfn(pteval)) && - !folio_test_large(folio)) - release_pte_folio(folio); + if (pte_none(pteval)) + continue; + pfn = pte_pfn(pteval); + if (is_zero_pfn(pfn)) + continue; + folio = pfn_folio(pfn); + if (folio_test_large(folio)) + continue; + release_pte_folio(folio); } list_for_each_entry_safe(folio, tmp, compound_pagelist, lru) { _ Patches currently in -mm which might be from vishal.moola@gmail.com are